1. Field
Apparatuses and methods consistent with exemplary embodiments relate to an optical apparatus and a method of manufacturing the same, and more particularly, to a light screening apparatus and a method of manufacturing the same.
2. Description of the Related Art
An optical screening apparatus is any type of apparatus for screening light. An optical shutter, which is one type of optical screening apparatuses, selectively allows light to pass therethrough. For example, the optical shutter in a camera may block or allow the passage of light that has passed through a camera lens toward an image sensor. In addition, the optical shutter may control at least one of a time at which the light is received and an amount of light to be received by adjusting at least one of an operation speed and a screening area of the camera lens (i.e., an opening size of the camera lens). The optical screening apparatus such as the optical shutter may be applicable to any electronic devices other than cameras (e.g., an optical switching device) which utilize a temporal, permanent or selective light screening function.
The optical shutter may be classified into a mechanical type and an electronic type. The electronic optical shutter enables to control at least one of an image sensor to receive light and the time of the image sensor's receiving of the light by controlling an operation state of the image sensor. Since the electronic optical shutter is driven by circuitry, the electronic optical shutter has been generally used for a portable digital camera having a limitation in camera module size. However, as the number of pixels of a camera module in the electronic optical shutter increases, moving object distortion may occur.
In light of recent increases in the resolution of the camera module embedded in a mobile device, attention has again been drawn to a mechanical optical shutter. Since electronic devices including digital cameras are becoming compact and thin, the mechanical optical shutter must also be small and thin and provide a quick response (i.e., shuttering) speed. Korean Patent Application No. 2009-0055996, titled “SHUTTER AND MICROCAMERA MODULE HAVING THE SAME,” incorporated herein by reference in its entirety, introduces an example of a mechanical optical shutter which can provide a quick response speed using a plurality of roll-up blades.
The mechanical optical shutter may be driven by an electrostatic force. To be specific, when a driving voltage is not applied, the mechanical optical shutter maintains a roll-up blade in a roll-up condition, and at this time, light is allowed to pass through a light transmission portion of a substrate. In addition, when a driving voltage is applied between a lower electrode (e.g., a transparent substrate) and an upper electrode (e.g., a roll-up blade), an electrostatic force is generated, thereby flattening the roll-up blade. The flattened roll-up blade blocks the light transmission portion of the substrate, and thus the light can be screened.